Tether station



Sept. 11, 1962 T. WYATT TETHER STATION Original Filed Aug. 29, 1957THEODORE WYATT INVENTOR Q m cwa/a ATTORNEY 8 r' 3,053 ,481 Ice PatentedS p 1962 5 Claims. (Cl. 244-1717) This invention relates generally to ahelicopter tether station; more particularly, it relates to a tetherstation for a hovering robot helicopter employed as a component of aradar system.

This application is a division of applicants copending applicationSerial Number 681,148, filed August 29, 1957, and entitled Radar System.

It is an object of this invention to provide a robot helicopter tetherstation having means therein to control the extent of elevation of saidhelicopter.

A further object of the invention is to provide a robot helicoptertether station having means therein to cool the helicopter power cable.

It is also an object of the present invention to provide a robothelicopter tether staion having means to protect the helicopter when thesame is not in actual use.

Other objects and many of the attendant advantages of this inventionwill be readily appreciated as the same becomes better understood byreference to the following detailed description when considered inconnection with the accompanying drawing, wherein:

The FIGURE is a sectional view, partly in elevation, showing a tetheredhelicopter nested in a tether station constructed according to thisinvention.

The present invention relates to a helicopter tether station for usewith the radar system described in applicants copending applicationSerial Number 681,148. Briefly, the radar system described in saidcopendin-g application contemplates a remotely powered and controlledtethered helicopter which is elevated by a conventional helicopter bladeor propeller system driven through a known type transmission. Anelectric motor, driving through the transmission, provides power for theblades. The helicopter body contains an antenna which is presentedtoward a radome carried in the wall of the body. The entire body may berotated with respect to the motor and its transmission, whereby theantenna may be caused to sweep 360. Portions of the radar transmitterand receiver are carried within the body of the helicopter and otherportions or components are positioned in the ground station or onshipboard, connections between the helicopter components and those onthe ground or shipboard being maintained through a cable which alsoserves to tether the helicopter above the ground radar station or ship.It should be understood, however, that some data and control functionscan be transmitted up to the helicopter or down to the ground or shipbase by the cable or by radio link. The choice can be made to suit thespecific design and ap plication.

In order to keep the size of the cable as small as possible so as tominimize the cable aerodynamic forces and to keep the weight of thecable at a minimum, the current passed through the conductors thereof ishigher than usual practice dictates, causing said cable to operate at atemperature just safely below the limit of high temperature insulatingmaterials. The elevated temperature of the cable precludes iceformation, but, as discussed below, requires the provision of coolingmeans when it is confined or stored in a manner preventing atmosphericcooling.

Referring to the drawing, a tether station constructed according to thepresent invention is shown in the figure. The tether station shown is ashipboard installation, the deck of the ship being designated at B, thehelicopter at 10, and the station generally at C. The helicopter 10carries a radome '15 in its side wall. Within the helicopter andconfronting the radome is a radar antenna 16. The tether station C isbest located in a cleared area, such as on the fantail of the ship, andinoludes a circular receptacle 21 comprising a side wall which has astraight upper portion, an inclined lower portion and a bottom wall 22.Positioned below the bottom wall 22 is a cable stowage tank 23. Abovethe wall 22 there is located a housing 24 which encases a chamber 25enclosing a powered capstan 26 and idler 27, a funnel-shaped cableopening 28, commonly referred to as a hawse, being positioned in the topwall of the housing 24. Power for the capstan 26 may be supplied by amotor (not shown). An inlet nozzle 29, connected to a source of water,is mounted on the side wall of the chamber 25 and extends through theside wall of the housing 24. Water flow is provided for cooling thecable 20, which would otherwise become overheated in the tank 23. Analternative design might incorporate a conventional cable drum and waterSprays. For leading the cable 20 into the tank 23 there is provided aguide tube 30. A shock absorber ring 31 overlies the top wall of thehousing 24 for cushioning the helicopter when in position in the tetherstation C. *Clam' shell doors 32 are mounted on the side wall of thereceptacle 21 and are movable in slots from the broken line positons tothe positions shown in full lines, for protecting the helicopter bodywhen in tethered position from heavy seas or from accidental blows fromother objects on the ship.

With the helicopter in tethered position the cable 20 extends throughthe hawse 28, about the powered capstan 26, through the guide tube 30and into the stowage tank 23. An end portion of the cable is passedthrough a suitable gland 33 in the side wall of the'tank and connectedto a power source (not shown) and to shipborne radar components. By theuse of capstan 26, the tank 23 and associated structure, it is possibleto insure proper cooling and storage of the cable 20 to prevent failurethereof from excessive temperatures. Moreover, the cable stowagearrangement eliminates the use of slip rings for transferring power atthe tether station, and no level wind mechanism, which would be requiredwith a winch drum, is needed. The idler 27 is adjustable and is employedas a constant tension brake for maintaining the cable 20 under a desiredamount of tension at all times.

In operation, prior to elevation of the helicopter from the tetherstation C, assuming shipboard operation, the clam shell doors 32 areretracted and the helicopter 10 is prepared for flight. Power is thenapplied, through the cable 20, to the motor of the helicopter forrotating its blades. After the motor has been brought up to speed thehelicopter will exert full lift on the cable 20, against the restrainingeffort exerted by the idler 27 under control of the operating personnel.As the restraint is released the helicopter will rise above the ship ata rate under the control of the operating personnel, and as sufficientcable is payed out to permit its altitude to increase, the helicopterwill cease to respond to any ship motion and will assume a steadyaltitude. The helicopter will continue to climb until the cable isbraked at the capstan at the desired altitude, say 1,000 or 2,500 feet.During elevation of the helicopter the radar equipment therein and onthe ship would be placed in operation.

Landing of the helicopter may be accomplished by applying power to thecapstan and winding in the cable 20 while maintaining said helicopterunder full power and stabilization. When fully lowered the helicopterwill rest on the shock absorber ring 31, when the blades may be brakedto a stop and the power disconnected.

While the tether station of the instant invention is herein described inassociation with a ship it is obvious that, as stated hereinabove, thesame is also capable of installation and use in other environments, suchas on land.

Obviously many modifications and variations of the present invention arepossible in the light of the above teachings. It is therefore to beunderstood that within the scope of the appended claims the inventionmay be practiced otherwise than as specifically described.

What is claimed is:

1. A helicopter tether station including a receptacle adapted to receivea tethered helicopter, a housing attached to and in communication Withsaid receptacle and containing a powered capstan and an idler, saidcapstan being fixedly mounted within said housing and said idler beingmovably mounted within said housing and disposed in opposition to saidcapstan, whereby said capstan and said idler will cooperate toalternately pay out and wind in a cable, a cable stowage tank attachedto and in communication with said housing, and nozzle means disposedwithin said housing and adapted to spray cooling fluid over that portionof a cable that may be disposed within said housing and said stowagetank.

2. A helicopter tether station as recited in claim 1, including a ringof shock-absorbing material disposed within said receptacle and adaptedto absorb shock between said helicopter and said receptacle.

3. A helicopter tether station as recited in claim 1, including clamshell doors associated with said receptacle and movable to enclose andprotect a tethered helicopter disposed therein.

4. A helicopter tether station including, in combination; a receptacleadapted to receive a tethered helicopter; a housing disposed centrallyof and attached to said receptacle, a cable stowage tank disposed belowand attached to said housing, said housing being placed in communicationwith said receptacle by a first opening disposed centrally in the top ofsaid housing and with said tank by a second opening disposed in thebottom of said housing, a powered capstan fixed within said housing, anidler disposed within and attached to said housing and movable towardand away from engagement with said capstan, a cable, one end of saidcable being attachable to a helicopter and the other end of the cablepassing through said first opening, around said powered capstan, throughsaid second opening, and into said tank, said capstan and said idlercooperating to alternately pay out and wind in said cable, and meansincluding a nozzle disposed within said housing for cooling that portionof said cable disposed within said housing and said tank.

5. A helicopter tether station as recited in claim 4, wherein said firstopening is a hawse, and including a guide tube disposed within said tankin communication with said second opening for guiding said cable intosaid tank.

References Cited in the file of this patent UNITED STATES PATENTS803,573 Eubank Nov. 7, 1905 2,429,502 Young Oct. 21, 1947 2,840,627Lewis June 24, 1958 FOREIGN PATENTS 447,824 France Nov. 8, 1912

